Science – Page 48 – a sibilant intake of breath

Rebutting Wente

Writing in The Globe and Mail, World Wildlife Fund President Gerald Butts has done a good job of expressing what is and is not important about the recent errors in IPCC reports that have gotten so much attention and rekindled the fires of the climate change denier community:

Yes, some scientists showed poor judgment in private e-mail exchanges later hacked and made public. Yes, some errors in fact and incomplete citations have been found in the IPCC’s 1,000-page reports. That said, even scientists who have criticized the IPCC agree that anthropogenic climate change is both a fact and an urgent threat to the planet.

All independent reviews undertaken so far (by The Associated Press, the University of Michigan and The Economist, for example) agree that none of the stolen e-mails or errors bring into question the science supporting climate change. To conclude otherwise is to misunderstand the process and power of science, and to dismiss the need to draw on the best available evidence and consensus to guide national policies.

Science is not a cold body of facts, but an organized system of inquiry, discovery, evaluation and learning. Science not only welcomes the correction of errors, its key attribute is that it is self-correcting over time. As new research arises, old hypotheses gain or lose support. While this process never stops, generally accepted conclusions do accumulate, based on the overwhelming weight of evidence. The fact and threat of anthropogenic climate change are clearly among those conclusions.

It is encouraging to see such an effective rebuttal printed to Margaret Wente’s misleading recent column, though it remains dispiriting that The Globe and Mail is still happy to give a platform to people as irresponsible and scientifically illiterate as Wente and Rex Murphy. Wente’s column is a prime example of a position that – on first glance – appears prudent, in suggesting that we shouldn’t take serious action while there still seem to be scientific uncertainties about climate. Unfortunately, the known characteristics of the climate system make this position irresponsible. The full effect of emissions today will take decades to fully manifest, and the climate system has the capacity to amplify small changes into much larger outcomes. What we know about the history and character of Earth’s climate tells us we need to take action now, not at some future point when the faulty claims of deniers have finally been deflated in the eyes of the public.

I suspect that, a few decades from now, people will be puzzled about why we were so unable to separate signal from noise, when it came to hearing what scientists were saying about climate change. Part of that is surely the result of actions taken in bad faith by those seeking to prevent policy action (people quite capable of exploiting the peculiar phenomenon that arise at the intersection of science and the media). That said, much of the explanation has to lie with the complacency of a public happy to hear that no action is required at the moment, no matter how thin the credibility of those making this announcement.

Climate change and animal migrations

In the wake of recent scandals in climate science, many people seem to have forgotten that unambiguous evidence for climate change is everywhere: including in the changing locations of species. The locations of thousands of species have been tracked, including plants, animals, and insects. Since 1950, they have been moving northward at a rate of about 6.5 kilometres per decade. Meanwhile, the lines denoting regions with a given temperature range (isotherms) have been shifting north at 56 km per decade. Gardeners and birdwatchers can tell you that the climate is changing.

A colony of Galapagos sea lions have migrated 1,500 km. Meanwhile, other plants and animals are moving poleward and uphill. When species get pushed to the edges of continents or the top of mountains, they will be in grave danger. Likewise, when animals are forced to move northward faster than the plants they depend on can do so, it strains food webs.

Say what you will about the personal conduct of climate scientists, the evidence of a changing climate is everywhere. Hopefully, human beings will understand this and begin to curb it before too many species are pushed to the wall, and before our own becomes too threatened.

Latent heat and storms

When energy is used to heat something up, the temperature does not increase smoothly as the energy is put in. Most significantly, this is because causing matter to change states takes energy in itself, above and beyond the energy that goes into warming. Imagine a big block of ice at 0°C. A lot of energy has to go into it before it becomes a pool of water at 0°C. The same is true for turning 100°C water into 100°C steam. Latent heat has been discussed here before.

Because of climate change, the overall trend in global air temperatures is going upward. As anyone who has visited a steam room or had a camera fog up when coming inside on a cold day knows implicitly, warmer air can hold more water. As well as being an important feedback effect (since water vapour is a greenhouse gas), warmer more air-laden water contains more of the latent heat that provides the energy for thunderstorms, tornadoes, and hurricanes. The increase in the average amount of latent heat in a body of air increases the probable strength of future storms, a fact that becomes especially worrisome when you acknowledge how the damage caused by storms increases in a non-linear way. Winds that are 10% faster have a third more destructive potential.

The extra water in the air will also increase the quantity of precipitation and the likelihood of floods. Furthermore, melting ice sheets will cool sea water, increasing the temperature differential between the equatorial and polar regions. This will increase the strength of mid-latitude cyclones, as air currents cooled by melting ice sheets (latent heat, again) collide with ever-warmer masses of air, containing ever-more water. The level of melting in the ice sheets is already significant enough to measure using sensitive gravitational data from satellites like GRACE. Greenland is losing about 100 cubic kilometres of ice per year, while West Antarctica is losing it at a somewhat smaller rate. The ‘wet’ process of ice sheet disintegration suggests that the rate of ice loss could increase dramatically, one the ice sheets are pushed past a critical point by warming.

Storms of My Grandchildren

Writer Robert Pool has defined a ‘witness’ as “someone who believes he has information so important that he cannot keep silent.” In the preface to his book, Storms of My Grandchildren, climatologist James Hansen identifies himself using the term. It is truly worrisome to be living in an age when such a prominent climate scientist sees his role in this way – and sees himself as having uncovered information of such importance that he cannot remain an adviser on the political sidelines. Storms of My Grandchildren is the most frightening thing I have ever read, and may end up being one of the most important.

James Hansen explains why we know as much as we do about the climate: not from computerized climate models, but from the evidence of climatic history laid down in ice cores and sediments. The story they tell is one of a dynamic system capable of amplifying small initial changes, and one in which rapid swings have taken place. Hansen identifies the greatest risks from climate change as the destabilization of ice sheets and the loss of biodiversity accompanying the many effects of climate change. On sea level rise, he explains:

If humanity burns most of the fossil fuels, doubling or tripling the preindustrial carbon dioxide level, Earth will surely head toward the ice-free condition, with sea level 75 meters (250 feet) higher than today. It is difficult to say how long it will take for the melting to be complete, but once ice sheet disintegration gets well under way, it will be impossible to stop. (p. 160 hardcover)

Hansen also highlights how positive feedback effects could lead to a runaway climate change scenario, and how the methane locked up in permafrost and methane clathrates has the potential to stack a second gigantic warming on top of the anthropogenic greenhouse gas warming, in the event they ever substantially melt:

[T]he world, humanity, has reached a fork in the road; we are faced with a choice of potential paths for the future. One path has global fossil fuel emissions declining at a pace, dictated by what the science is telling us, that defuses the amplifying feedbacks and stabilizes climate. The other path is more or less business as usual, in which case amplifying feedbacks are expected to come into play and climate change will begin to spin out of our control. (p. 120 hardcover)

In the most extreme case, in which all coal and unconventional oil and gas are burned, the stacked-up positive feedbacks could be sufficient to boil away the oceans, eventually leaving Earth in a state similar to that now inhabited by Venus, a planet formerly adorned with liquid water before a brightening sun induced runaway climate change there.

In addition to the scientific story, Hansen tells some of his own: about the censorship he witnessed at NASA, about his recent civil disobedience actions against mountaintop removal coal mining, about is perceptions of American politics, and about the grandchildren whose prospects have left him so concerned. Sometimes, these asides can seem secondary to the main thrust of the book, though they do underscore the extent to which this is an impassioned personal plea, not a technical scientific assessment. The insight into the scientific process and the operation of the Intergovernmental Panel on Climate Change (IPCC) are also interesting.

The most dubious part of the book may be Hansen’s optimism for fourth-generation fast breeder reactors. He highlights their possible advantages, namely in terms of stretching our uranium fuel supplies, but doesn’t give serious consideration to the practical and economic issues with a massive nuclear deployment. He is also overly pessimistic about renewable forms of energy. I would recommend that he take a look at David Mackay’s excellent book on different routes to a zero-carbon energy future. People who read Hansen’s book may also be well-advised to do so.

Hansen makes some key points about climate policy: notably, that emissions targets and cap-and-trade schemes are meaningless, if governments continue to allow coal use and the exploitation of unconventional oil and gas to continue. Those are the fuels that contain enough carbon to threaten all life on Earth; meaningful climate policy must, among other things, ensure that they remain underground. As an alternative to cap-and-trade schemes that are potentially open to manipulation and which offer no incentive to cut faster than prescribed by the cap, Hansen endorses a fee and dividend system where a tax is applied to all fossil fuels at the point of production or import. His overall view is not so different from the fantasy climate change policy I wrote earlier, though I hadn’t been fully aware of all the risks Hansen enumerates when I wrote it.

In the end, Hansen has provided as clear and compelling a warning as anybody could ask for. We are putting the planet in peril and endangering the lives and prospects of future generations in a deeply immoral way. Governments are misleading people with the sense that they are handling the problem when, in reality, even states taking climate change seriously are doing nowhere near enough to ensure that catastrophic or runaway climate change goes not occur. We need to change the energy basis of our society, and keep the carbon in coal and unconventional fossil fuels in the ground. In so doing, we may be able to stop the warming we are inducing, before it generates the devastating feedbacks that are the key message of Hansen’s book.

Those interested in reading this book should consider taking me up on my offer for a free copy. For those unwilling to commit the time to go through a 275-page book, Hansen has a more concise presentation online in PDF form.

Partly prompted by this book, I am in the middle of starting up a new personal project, intended to help with the planet-wide coal phaseout that is necessary. I will make more information on it public, once it is developed further.

[16 February 2010] Now that I have a fuller understanding of the importance of not burning coal and unconventional fossil fuels, because of their cumulative climatic impact, I have launched a group blog on the topic: BuryCoal.com. Please consider having a look or contributing.

Tackling coal emissions

Speaking of taking action against climate change, a strong case can be made that the single most important thing we can do to reduce the chances of catastrophic climate change is to phase out coal. Coal is the one fossil fuel that is definitely abundant enough to cause catastrophic climate change. As such, we need to:

Prevent the construction of new coal plants that emit carbon dioxide, including in the developing world
Convert existing coal plants to run on biomass, greatly reducing their net climate impact
Encourage the early shutdown of existing coal facilities, partly through a carbon price
If possible, develop carbon capture and storage technologies

What actions can we as individuals undertake to advance the decline of emissions-intensive coal, both in Canada and around the world?

Is runaway climate change possible? Hansen’s take

Back in 2008, I wrote about whether ‘runaway’ climate change might be possible on Earth. At one point, Venus had liquid water on its surface. Then, the sun grew brighter and Venus warmed. Its oceans evaporated and huge amounts of carbon dioxide (CO2) got baked out of the crust. The heat made the water break up into hydrogen and oxygen: the oxygen bonded with carbon to make more CO2, and much of the hydrogen escaped into space. Venus became permanently hostile to life, with surface temperatures of 450°C.

Could burning all of Earth’s fossil fuels produce the same outcome?

Some people take comfort from the fact that there have been times in the history of the planet when greenhouse gas concentrations were much higher than now. The world was very different, but there was no runaway greenhouse and life endured. James Hansen devotes the entire tenth chapter of Storms of My Grandchildren to considering whether this assessment is valid. Three things give him pause:

The sun is brighter now than it was during past periods with very high greenhouse gas concentrations. The 2% additional brightness corresponds to a forcing of about 4 watts per square metre and is akin to a doubling of CO2 concentrations.
For various reasons, the greenhouse gas concentrations in past hot periods may not have been as high as we thought.
We are introducing greenhouse gases into the atmosphere far more quickly than natural processes ever did. This might cause fast (positive) feedback effects to manifest themselves forcefully, before slower (negative) feedback effects can get going.

He also explains that the sharp warming that took place during the Paleocene–Eocene Thermal Maximum (PETM) were not caused by fossil fuels (which remained underground), but rather by the release of methane from permafrost and clathrates. If human emissions warm the planet enough to release that methane again, it could add a PETM-level warming on top of the warming caused by human beings.

Hansen’s conclusions are, frankly, terrifying:

The paleoclimate record does not provide a case with a climate forcing of the magnitude and speed that will occur if fossil fuels are all burned. Models are nowhere near the stage at which they can predict reliably when major ice sheet disintegration will begin. Nor can we say how close we are to methane hydrate instability. But these are questions of when, not if. If we burn all the fossil fuels, the ice sheets almost surely will melt entirely, with the final sea level rise about 75 meters (250 feet), with most of that possibly occurring within a time scale of centuries. Methane hydrates are likely to be more extensive and vulnerable now than they were in the early Cenozoic. It is difficult to imagine how the methane clathrates could survive, once the ocean has had time to warm. In that event a PETM-like warming could be added on top of the fossil fuel warming.

After the ice is gone, would Earth proceed to the Venus syndrome, a runaway greenhouse effect that would destroy all life on the planet, perhaps permanently? While that is difficult to say based on present information, I’ve come to conclude that if we burn all reserves of oil, gas, and coal, there is a substantial chance we will initiate the runaway greenhouse. If we also burn the tar sands and tar shale, I believe the Venus syndrome is a dead certainty.

To re-emphasize the point, averting catastrophic or runaway climate change is the most important ethical and political task for those alive now, even if most politicians don’t yet realize it or don’t yet understand what that involves.

That last line also offers something to throw back, next time someone says the billions of dollars of revenue from exploiting the oil sands are simply too valuable to not collect.

Climate change: the solar hypothesis

There are some who assert that the global warming that has been observed on all continents is caused by changes in the output of the sun. This hypothesis does not stand up to scrutiny in either the short or the long-term, as made clear in James Hansen’s Storms of My Grandchildren as well as published papers of his, including “Target Atmospheric CO2: Where Should Humanity Aim?.” It is important to remember that what follows does not come from climate models, but rather from data on the paleoclimatic history of the planet, collected from ice and ocean cores and other sources.

The 12-year solar cycle

The sun dims and brightens across a twelve year cycle. While each square metre of the planet absorbs about 240 watts of sunlight averaged over day and night, the recorded magnitude of these cycles is about 0.2 watts. Not all forcings have the same effect on the climate. Taking the forcing caused by carbon dioxide (CO2) as the baseline, it can be calculated that the solar cycle forcing has an effective strength of between 0.2 and 0.4 watts. The climate forcing due to the 1750-2000 CO2 increase is about 1.5 watts. Other human-caused changes, such as adding methane, nitrous oxide, CFCs, and ozone to the atmosphere, make the total greenhouse gas forcing about 3 watts.

Each year, we are increasing the concentration of carbon dioxide in the atmosphere by about 2 parts per million (ppm). That equates to an effective forcing of 0.03 watts. As such, seven years of carbon dioxide emissions at the current level would offset the cooling effect of the sun being at the lowest ebb of its cycle. As a consequence, human-made climate change now overwhelms this natural cycle.

Long-term trends

Longer-term data also shows how greenhouse gases are more important to the climate than changes in solar output. The geological era spanning the last 65 million years is called the Cenozoic. Over that time, the sun’s output has increased by 0.4%. This corresponds to an increase of about 1 watt since the dinosaurs died out. Over this time period, the planet has actually cooled considerably: with mean global temperature more than 8°C higher at the end of the time of the dinosaurs. This, despite the increased solar output.

Over this timespan, the atmospheric concentration of CO2 has ranged from between 1,000 and 2,000 ppm during those hot years of the early Cenozoic and as little as 170ppm during recent ice ages. This range corresponds to a climate forcing of about 12 watts: at least ten times more than the forcings from the sun and from changes in the configuration of continents. As Hansen says: “It follows that changing carbon dioxide is the immediate cause of the large climate swings over the last 65 million years.”

The following diagram deserves consideration:

It shows temperatures from the Cenozoic: data that was obtained by examining the shells of microscopic animals called foraminifera. It shows the slow decline in mean global temperature over the whole span, as well as evidence that abrupt changes in temperature are possible.

What we’re doing now

One thing to consider is that if we keep increasing our greenhouse gas emissions, we will push carbon dioxide concentrations way above pre-industrial levels and into the range that existed at the beginning of the Cenozoic. While the cooling trend that we are living at the end of happened over tens of millions of years, temperature increases of well over 4°C could occur by the end of the century, with further warming beyond. While life has had ages to adapt to climate change as it was occurring before humanity, we are presiding over a spike in temperatures and greenhouse gas concentrations.

This graph shows CO2 concentrations from the last 400,000 years, as measured in ice core samples:

Keeping all that in mind, it seems very sensible to be working hard to keep the tip of that spike from getting too high. We should be worrying about our emissions, not blaming the warming we have observed on the sun and moving on.

Why we cannot wait for climate science to be completely settled

To those who say that we should just wait and see how the climate changes, without taking action to reduce our emissions, I offer the following analogy:

To assume the best possible outcome, and to make plans only on that basis, is akin to the United States assuming they would be ‘greeted as liberators’ in Iraq. Even if things had unfolded that way, it would have been irresponsible to make plans only on that basis. If they had drawn up contingency plans, and taken pre-emptive actions, on the grounds that serious opposition was possible, nobody would have thought that behaviour inappropriate, even if the outcome ended up being better than feared.

Arguing that we should wait for the science to be completely settled means waiting until climate change has actually taken place. Given the complexity of the climate system, and the fact that we only have one planet to work with, there is no way we can ever be 100% confident that our models and projections are correct. Therefore, to delay action until we have certainty is to delay action until it can no longer have any effect. It is akin to starting your contingency planning long after the war has ended.

Bright-Sided

From Oprah to New Age philosophy, ‘positive thinking’ has become a hugely influential movement in business circles, the religious sphere, in pop medicine, and elsewhere. In Bright-Sided: How the Relentless Promotion of Positive Thinking Has Undermined America, Barbara Ehrenreich makes the case that the movement is poorly thought out and damaging. Her arguments are convincing, especially when it comes to situations where positive thinking is used to blame the victim when they suffer as the result of developments beyond their control: be it the movement towards corporate downsizing (which corresponded with the rise of motivational speakers in the workplace) or the unjustified assertion that cancer patients are responsible for their own worsening or recovery, on the basis of the mental attitudes they maintain.

Ehrenreich highlights how relentless optimism leads to dangerous groupthink, in which risks are downplayed and those who raise legitimate worries are sidelined. She provides ample evidence that these factors played a role in the inflation of the global house price bubble, and have continued to have important economic and political effects. These include the weird state of deluded isolation in which society’s richest people now reside. She also spends considerable time discussing the warped theology in which god is seen as a sort of mail-order service, happy to send you whatever good things (houses, cars, promotions) you are able to ‘manifest’ for yourself, simply by fervently desiring them.

Positive thinking involves a weird reversal, when it comes to dealing with risks. They cease to be external (concern that your company might fire you to improve their short-term profitability) and become entirely internal (fears about what your state of mind might do to you). It is also tied fundamentally to the notion that happiness is not most important in itself, but rather insofar as it influences events: “Nothing underscores the lingering Calvinism of positive psychology more than this need to put happiness to work – as a means to health and achievement, or what the positive thinkers call ‘success.'” The former tendency puts people in danger of worrying about the wrong things, while the latter strategy puts them at risk of seeking to achieve particular outcomes in nonsensical ways. That is especially dangerous when it comes to making big purchases on credit, firm in your belief that the universe will provide you with the means of dealing with it later.

Ehrenreich’s points are well-taken, though the book can be a bit tedious to read at times. There are also some partial contradictions. It is repeatedly asserted that there is no medical evidence that thinking positively improves health outcomes, yet it is taken as plausible that George Beecher was able to speed his demise through negative thinking. In the course of her analysis on the medical evidence, Ehrenreich claims to be “not in a position to evaluate” evidence that those with a positive outlook may have some protection against heart disease, but is seemingly happy to evaluate research on other illnesses that confirms her hypothesis.

All told, Ehrenreich makes important points about the poisonous institutional culture that accompanies an excessive focus on positivism – and the view that individuals are almost entirely responsible for what happens to them. Her concluding call for ‘realistic’ thinking is certainly appropriate enough, though perhaps she does not go far enough in suggesting how the empire of positive thinking she has mapped the outlines of might be deconstructed. As the world continues to grapple with real problems, magical thinking cannot be a substitute for dispassionate analysis, risk management, and contingency planning. How we get from our world to one more like that, however, remains mysterious.

LIDAR for wind turbines

This is a neat idea: wind turbines that use LIDAR (akin to RADAR, using light) to anticipate the strength of wind, and prepare for it in advance:

Dr Mikkelsen and his colleagues worked out that they could use lidar to scan incoming wind and determine how it was behaving before it struck the turbine. To try this idea out, they first placed lidar devices at the base of 120-metre-tall wind turbines at Hovsore, the Danish test site for such devices. The lidars scanned the approaching winds with a laser that produced infra-red light with a wavelength of 1.55 microns. Reflected light was detected by a device so sensitive that it could pick up one returning photon (the quantum-mechanical particles of which light is composed) out of every thousand billion fired by the laser. The device measured wind movement at 40, 60, 80, and 100 metres above the ground, and 100-200 metres in front of the turbine. The data it collected were then compared with wind measurements taken by cup anemometers (the sort that spin when struck by wind, to record its speed) in order to calibrate the lidar. That done, the computer which analyses the lidar data can be connected to the motors that adjust the pitch of the turbine blades, in order to maximise energy production and reduce damage.

Such technologies could help deal with minute-to-minute changes in wind speed, improving the reliability of wind farm output.